Simple periprocedural precautions to reduce Doppler microembolic signals during AF ablation.

Background: Doppler microembolic signals (MES) occur during atrial fibrillation ablation despite of permanent flushed transseptal sheaths, frequent controls of periprocedural coagulation status and the use of irrigated ablation catheters PURPOSE: To investigate the number and type of MES depending on the procedure time, prespecified procedure steps, the activated clotting time (ACT) during the ablation procedure and the catheter contact force.

Methods: In a prospective trial, 53 consecutive atrial fibrillation patients underwent pulmonary vein isolation by super-irrigated "point-by-point" ablation. All patients underwent a periinterventional, continuous transcranial Doppler examination (TCD) of the bilateral middle cerebral arteries during the complete ablation procedure.